Comparative Accuracy of Activity Scores of Intestinal Ultrasound and Colonoscopy in Monitoring Ulcerative Colitis Activity

Ulcerative colitis (UC) has a relapsing-remitting course which necessitates frequent follow-up examinations to monitor disease activity.

Disease management was previously guided by patient reported symptoms, and treatment targets were based on symptom control. However, the patient's symptoms do not necessarily correspond to inflammatory activity and current guidelines recommend that management should be based on objective evaluations.

Ileocolonoscopy is considered the reference standard method for determining disease status in Ulcerative colitis. Although validated and reproducible scoring systems are complex and cumbersome to use in clinical practice, and even though ileocolonoscopy is an excellent tool for activity monitoring, it cannot be performed on a regular basis as it is invasive, is resourceintensive and causes considerable patient discomfort. As numerous follow-up examinations are required, simple non-invasive surrogate markers are needed.

Biomarkers such as C-reactive protein \[CRP\] and faecal calprotectin are well established in both primary work-up and disease monitoring.

Still, as they cannot depict disease location and have limited accuracy, additional tools are required.

Gastrointestinal ultrasound \[GIUS\] has high diagnostic accuracy for detecting active CD, and in trained hands, it can make significant impact on clinical decision-making.

Furthermore, as it is non-invasive, readily available and can be performed bedside, the modality seems well suited for bedside and frequent activity monitoring.

Still, interpretation of the GIUS findings may be influenced by the sonographer's level of experience. A standardized ultrasound activity index may simplify the interpretation of the sonographic findings, allowing for easier comparison between different examinations during follow-up. Although various sonographic activity scores are available, the methodology for development was shown to be insufficient in most studies and no index is in widespread clinical use.